Leak-resistant fiberglass tank and method of making the same

Abstract

A tank for use in storing volatile liquids and, in particular, petroleum distillates, such as gasoline in an underground environment, includes a fiberglass outer wall lined with a corrosion-resistant impervious film liner that substantially covers the entire interior surface of the fiberglass tank. In a preferred method of constructing the tank, a lay-up mandrel has an end cap of the film placed over a first end thereof and pressed to fit closely the exterior surface topography of the mandrel. A strip of film is laid down on the mandrel overlying at least a portion of the end cap and the film strip is wound in a helical fashion such that at least portions of adjacent coils of the helix overlap one another until the mandrel is essentially completely covered by the film. The polyester resin and glass fibers are then laid down over the film and cured in place. The mandrel is then removed, leaving a film-lined fiberglass tank. In a preferred embodiment, the film is comprised of polyvinylfluoride or polyester terephthalate.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. A tank for the underground storage of petroleum distillate products having a fiberglass wall and an inner lining substantially completely covering the interior of said tank, said inner lining including a plurality of adjacent partially overlapping strips of corrosion-resistant film having resin between the overlapping portions of adjacent film strips and having the ends of the tank lining comprised of end caps constructed and arranged to accommodate the curvature of the ends of the tank, wherein the end caps are constructed and arranged with pleats, said pleats being foldable to conform to the shape of the end of the tank. 
     
     
       2. The tank of claim 1, wherein the adjacent strips of film are coils of a continuous helically wound strip of film. 
     
     
       3. The tank of claim 1, wherein said film is comprised of polyvinylfluoride. 
     
     
       4. The tank of claim 1, wherein said film is comprised of polyester terephthalate. 
     
     
       5. The tank of claim 1, wherein said lining comprises a plurality of parallel, annularly wound strips of film.